The use of ultrasounds in medicine requires, like all physical agents potentially harmful to human health, an accurate assessment of the risks to the health of patients. The nature and extent of these risks depend on exposure levels which in turn are differentiated according to the specific diagnostic or therapeutic applications. Intermediate exposure levels are associated to physiotherapic applications. To analyze specific issues relating to the effectiveness and safety of physiotherapic treatments, a review of the scientific literature and technical standards was carried out. At present, the actual effectiveness of ultrasound physiotherapy is still far from being clearly assessed: further clinical and experimental studies are needed in order to optimize therapies, determining the benefits and risks of treatments and deepening the understanding of the action mechanisms of the physical agent, even on the basis of a better characterization of those physical quantities mostly significant for biological effects. The examination of technical standards defining the security requirements of the equipment allowed the identification of some critical issues; on these bases some proposals are suggested for the improvement of quality and safety of treatments.